"I don't know how to delegate. I don't know how to do it," says the actor, who was responsible for casting each one of the film's many celebrity voices, including Chris Rock, Larry King, Sting, and Oprah Winfrey. "Many times with these movies the actor to will just go into a studio with a technician and just read the lines from the script, but I performed with every actor — and there are 45 actors in this movie … even if they had one line."

Two animated movie veterans, Matthew Broderick (The Lion King's Simba) and Zellweger (Angie in Shark Tale), were among those many actors.

"With animated movies, I have often never even met the other [performers]," says Broderick, who voices Barry's best friend, Adam. "It was different [working with Seinfeld], because we always did it together, because he was directing it, too."

Oscar-winner Zellweger (Cold Mountain) describes her character Vanessa, the human florist, as "eclectic" and "quirky." Asked why she thinks Seinfeld selected her for the part, Zellweger jokes: "I bet it is because we are neighbors, and he knew that I couldn't tell him 'no' if he needed extra hours, because he knows where I live."

The actress, best known for her live-action hits like Jerry Maguire and Bridget Jones's Diary, says doing voice work for animation is "scary": "I feel so exposed because there is nothing to hide behind. You don't have weird hair or funky makeup or a corset — it is all you in your sweats. And you have no idea how badly you could act in this stuff. You can just really ruin it. You can just slaughter the comic moment. You have to be really brave."

Jerry Seinfeld at Cannes. Click for more. Photo by Glenn Kenny

"Brave" certainly describes Bee Movie's industrious shepherd, who has been just as determined to get word out about his first animation feature as he has been in developing and producing it. Though NBC has been airing 22 live-action comedy vignettes to promote the film, Seinfeld, of course, had to push things further: In May, during the Cannes Film Festival, the actor dressed in a cumbersome bee costume and performed a high-wire act from the top of the eight-story Carlton Hotel.

"We practiced it at three o'clock in the morning so nobody would see us," he recounts. "It was fun at night, even though you couldn't see anything — it was all black. During the day it was scarier when I saw all those people on that pier, and you could see the ocean. But nobody knew about the movie before I did that."

Whether or not Seinfeld has managed to generate enough buzz around Bee Movie to outperform Disney's runaway summer smash Ratatouille remains to be seen. But the comedian will no doubt do everything he can to make that happen.